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polar red writes "22 years of banning CFCs is starting to pay off. Researchers have finally been able to measure a reduction in size of the ozone layer hole, after finding the source of its fluctuations. 'Salby's results reveal a fast decline in ozone levels until the late 1990s, then a slow rebound that closely matches what theoretical calculations had predicted, says David Karoly, a climate scientist at the University of Melbourne, Australia. "It is the sort of result that was expected, but is the first to provide detection of an increase in Antarctic ozone levels," he says.'"

The ozone disappearing was a much more pressing and obvious issue than global warming. I understand that we replaced one problem with another, but that's engineering. We went with the issue that would give us more time to solve. Besides, it would have been an issue anyway.

Global warming is caused by the emission of gases, mostly CO2, but also CFC replacements that are 1000s of times more potent than CO2.

Fixed that for ya. Apparently Nature doesn't provide free lunches:(

Oh no, Nature is charging for lunch now? Does she accept credit cards? Does "lunch" include the things necessary to create lunch, like the sun? Do I have to pay for the sun now?!? That sounds expensive.

But there 10's of thousands of times less CFC replacement gases in the atmosphere than CO2 so they are a minor component of GHG warming. By themselves they wouldn't cause enough warming to worry about. Adding them on top of CO2 and methane they don't help.

AND I'd like to add that it is also resistance from the population in general. Many people don't want to give up their internal combustion engines - that's what it's going to take to clean up the air, solve our oil dependency problems and pretty much do nothing about Global Warming because everything we do will be more than nullified by China, India, Indonesia, and all of the billions of people who are going to burn their coal, petroleum, and everything else they can.

We're pretty much fucked.

No, we just need a reasonable alternative to internal combustion engines. And by "reasonable", I mean "doesn't require people to completely rework their lifestyle into an inferior version".

I can't get to my place of employment without an internal combustion engine. There's no public transit to the area. It's in the middle of an industrial park filled with semis and heavy equipment, so riding a bike would be suicidal (not to mention a three-hour trip one-way, according to Google). Give me a way to do that wi

Well, for the usual commute, electric cars should do just fine. The only infrastructure update you would probably need are charging ports at all parking lots at your workplace and your home. That should take care of 90% of commutes. The longer-term solution would be rethinking city planning, which way too often is completely focused on cars. I live in a European city which mostly did it right. Living in the city, half an hour commute with public transit and yet, still lots of green areas around my home, so

Naturally that is part of the solution - there is nothing fundamentally impossible about that, though. You just gotta start at some point. Why not start with implementing an electric infrastructure that allows city traffic to go mostly electric. Apart from climate problems, you get the smog shit out of the way, even if you go with coal plants for now - the filtering is way simpler there. Then you can shift to renewables without changing your traffic infrastructure. 2-3 decades, and it can be done without pa

Maybe your infrastructure just sucks? I live in the first world, personally. In particular, in a country that hasn't let its grid go to shit for some decades. All I see is overcapacities. But you don't really want to argue about the possibility of changing the status quo, you are absolutely convinced that it should not be changed, therefor it CANNOT be changed. When your argument boils down to "electrification of commuter traffic will kill the elderly", well, then you'd better admit that you lost, before yo

Of course we will need to make overhauls - what are we even arguing about here? After all, it's not like every IC engine will be magically converted into electric overnight. The infrastructure change is not impossible, and not even fundamental. To say it can't work is like saying "We would have to exchange every stable for a gas station to get rid of horse buggies. This will never work" - well, it worked, on the timescale of two to three decades. On the same timescale the next transition can and will work.

ICE cars get about 25% efficiency from gasoline, and getting the gasoline from crude to their tanks eats at least another 7%.

Coal plants, while filthy, still generate electricity at over 35% (up to 45%) net efficiency that electric cars consume at over 95% net efficiency. That's at least 33% efficiency from coal/electric instead of 18% efficiency from gas/crude. ICE is therefore at most 54% (or as little as 42%) as efficient as the coal/electric transportation. When coal plants capture the "waste" heat from

China's 2011-2015 plan (its 11th 5 Year Plan) will reduce China's total energy consumption by 15%, and its total CO2(-equiv) emissions by 17%.

By the time China deprives the US of the "but China makes our efforts moot" fallacy that (literally) smokescreens US greed and filth, it will be too late for the US to catch up to China's lead in 21st Century industrialism. Way to blow it, deniers.

Now be careful. The CFC replacements are potent greenhouse gases [acs.org]. Potent as in 3 orders of magnitude worse than CO2. Is it better to die of skin cancer, or of hunger due to crop failures due to draught due to raising global temperature? I don't know...

First, some ozone-depleting compounds are even worse. For example, halons not only destroy the ozone layer but are also among the top global warming agents (by the virtue of their chemical unreactivity).

Second, the total amount of emitted CFC-replacement gases is not large, so we can generally ignore it for now.

The amount of CFC released into the atmosphere is insignificant against the sheer volume of CO2 (millions of tons of gas versus probably less than a ton of CFC). In addition Methane is even more potent than CFC's (IIRC it is 10 times more effective at trapping heat than CO2) and is an unregulated emission just like CO2. You could do more to stop global climate change by making natural gas illegal than you would ever cause by outlawing CFC's. In fact you probably emit personally more Methane through intestin

I seem to recall there being scientists back then arguing "CFC or no CFC, this will fix itself given a few decades, no reason to panic". By your logic, should we now believe whatever those people state?

The point I'm trying to make, as others have: correlation != causality.

I'm going to admit that my understanding of the situation is also based on me "recall[ing] there being scientists" saying certain things, one of which is that the ozone hole was directly caused by massive CFC usage. That directly refutes you and is the status quo belief. You are the one with the burden of proof.

Yes, without any proposed mechanism of causality, a correlation is just a correlation and does not imply causality. But with CFCs and the ozone layer, there is a mechanism of causality. CFCs catalyze the reaction of ozone molecules breaking up into oxygen molecules.

The fact that you even use 'oil people' in a statement and believe that all deniers are in that group shows just how much bias, and the methods you use to stifle debate on the issue. I'd be ashamed to use use that as an argument. But since many in the pro-AGW use this regularly, I'll just lump you as a religious nutbag. Your methods are similar.

You're right, there are also religious nut jobs that believe that God won't allow any flooding because the Bible doesn't foresee ones. And the libertarians that are opposed to any and all regulations on the basis of them being entitled to do whatever they like so long as there isn't an indisputable conflict with other people's rights. And then don't forget the people who don't actually have any education on the matter who are skeptics mainly because Fox News tells them to be afraid of the vast liberal consp

It's because most of the evidence supporting global warming thus far is comprised of correlation studies. As I like to say, a good correlation paper can win you a high school science fair. A good causation paper can win you the Nobel prize. Which is precisely what happened with ozone depletion [wikipedia.org]. A trio of scientists came up with an elegant, predictive, and empirically accurate mechanism to explain exactly how ozone depletion was occurring, and won the Nobel prize in Chemistry for it.

Come up with a comprehensive, predictive, and empirically accurate model for climate change, and you will probably win the Nobel prize (in something like physics, not a trophy prize like peace) and simultaneously convince the world's government that they must act. The problem with correlation studies is that they're always open to dispute since you never identify or test the actual mechanism causing the problem. That's what happened with cigarettes - for decades the medical community had tons of correlation studies saying that smoking was bad. But the government restrictions and bans didn't come about until medical researchers began to identify and confirm the mechanisms by which smoking was causing cancer.

The causation paper for climate change would win you zilch at all, since the basic mechanism has been published by Arrhenius about 130 years ago. All the open questions are more in the realm of systems theory, not in the realm of basic mechanisms.

The radiative equilibrium between incoming sunlight and blackbody radiation for Earth would result in a temperature about 20K lower than observed, when not taking atmospheric effects into account. Accounting for absorption and reemission by atmospheric CO2 you arrive at the actual average temperature. Said spectroscopic properties of CO2 are simply measurable in the lab. I actually did the experiment in a lab session about 14 years ago - part of the physical chemistry II lab. Are you seriously questioning the existance of the greenhouse effect as such?

You're not stating a falsifiable hypothesis. You're implying that because of a spectroscopic property of CO2 measured in a lab, that your hypothesis is true (that CO2 levels drive global warming). This is not necessarily the case: you're *assuming* the conclusion and *asserting* the relationship, not proving it.

I am seriously questioning your ability to state any real-world observations that would refute your hypothesis.

Oddly enough climate change is something that comes out of the physics models when you put in what we understand of the climate. It has nothing to do with correlation, it's pure mechanical causation. As it happens, the observations do confirm the model.

And it also happens, that the exact same people who were arguing against CFC -> Ozone hole causation and smoking -> lung cancer causation started arguing against climate change. They obviously can fool some of the people all of the time.

Oh, and the actual mechanism of how smoking causes lung cancer was partly revealed a few year back, but is still not completely understood.

As for the smoking -> cancer mechanism, large parts of it are known for decades. Polycyclic aromates in the smoke are potent intercalators, which put themselves between basepairs in DNA and mess with replication. Given how fast biochemistry has developed in the last century, that mechanism is positively prehistoric. There are other mechanisms, some of which have been found more recently, but the basics are known for ages.

The observation that would not fit the prediction would be little or no warming. The falsifiable hypothesis is that an increase in carbon dioxide in the atmosphere causes warming. There are literally hundreds of published scientific papers you can read about the topic. It's been a very active area of research for decades. I'll point you to just one short summary of the research results [norvig.com].

Okay, so say we get little or no warming for 5 years, while CO2 increases. Are you satisfied that CO2 doesn't drive temperature?

What about 10 years? 20 years? 50 years? What if we find an ice core record that shows 100 years of rising CO2 and falling temperatures?

We already have falsifications to the very basic "an increase in CO2 causes warming", because we've *observed* cooling during periods of increasing CO2. So now you've got to expand on your hypothesis to account for periods of cooling during in

You thoroughly refuted the hypothesis "CO2 is the only determining factor for global average temperature". Congratulations! Only, no one posits that hypothesis. Do not despair, noble Don Quixote - there are more windmills on the horizon that you can attack. Or are those even wind power plants? Charge, brave knight, CHARGE!

Why is it that the scientists can detect an ozone hole, provide a fix, show that the fix solved the problem

It's worth noting that the complete sequence described above hasn't actually happened. Sure, an ozone hole was detected, but we don't know that human activities have played a significant role in its existence, that is, it may something that occurs anyway without human interference and hence, we are at best very limited in our ability to fix it without some large scale geoengineering project.

Then the final claim in the sequence that the "fix solved the problem" is based on nothing but wishful thinking. He

I think the problem with the correlation != causation thing that is trotted out without fail is that people mistake it for correlation does not imply causation.

I'm no logician so feel free to rephrase that, but the essence is that just because correlation doesn't mean causation all the time doesn't suggest that correlation doesn't mean causation some of the time.

Of course it is correct - in the absence of other evidence. The implication is done by providing the mechanism. So may I suggest the corollary "In the presence of a physically connecting mechanism between two phenomena, correlation does imply causation"?

when there is a physical mechanism connecting two phenomena AND a correlation between them

Here's a simple game to try. Claim that someone has figured a relationship between two unrelated phenomena and ask an audience to guess what the connection is. Your audience will come up with numerous "physical mechanisms" for explaining the correlation they think might exist. Sure, having a physical mechanism (that is, a model for interaction in other words) and a correlation is better than a raw correlation, but it's a far cry from actual causation.

when emotions and political leanings enter the argument it is far to often to emerge wrong, not matter how right one may be.

You forgot economic interests. The problem with the climate change debate is NOT that there is too much emotion in it, it's that there is too much MONEY in pretending it's not real. The oil and coal industries throwing FUD against preventing climate change is precisely the problem with the debate.

I suppose there would still be people who prefer to distrust scientists and or disreguard "treehuggers" just as there were/are still people who pretended cigarettes were perfectly healthy long after the tobacc

If what you meant to say was "there's an awful lot of money in convincing people that [climate change] is real too" then I'd say:
For every dollar spent convincing people that climate change is real there is probably a hundred dollars spent trying to convince people that climate change is a myth.

The government-funded scientists are welfare queens. They use facilities paid for by taxpayers. How much money is spent on those facilities?

The budget of the entire US Department of Energy is approximately $25 billion, and it's by far the largest chunk spent on publicly-funded energy research. $10 billion of this is actually "nuclear security", i.e. keeping our nukes functional, which has nothing to do with global warming. The most expensive energy-research project currently in progress is the fusion reac

Between a conspiracy of the makers of solar panels, hybrid cars, nuclear power, and hippies, and a conspiracy on the part of coal and oil, I'm much more worried about the coal and oil conspiracy. They got more money.

Anyway, my point was mainly that economic interests confused the issue. If it goes for both sides, fine, just don't say it's all "emotion" and no logic.

I think this is the aspect of the debate that annoys me the most - the hyberbolic exaggeration of the economic effects of reduced consumption of fossil fuels. There are of course real costs involved, but nothing that scientists or mainstream policy-makers have proposed is going to cause us to sink to Third World levels of deprivation, or revert to a pre-industrial economy. Citizens of Western Europe have been living with drastically higher gasoline prices than us for decades, and they don't seem impoverished to me. Downgrading to a smaller and more fuel-efficient car is not a huge decrease in living standards relative to what the rest of the world has to endure.

I think this is the aspect of the debate that annoys me the most - the hyberbolic exaggeration of the economic effects of reduced consumption of fossil fuels. There are of course real costs involved, but nothing that scientists or mainstream policy-makers have proposed is going to cause us to sink to Third World levels of deprivation, or revert to a pre-industrial economy. Citizens of Western Europe have been living with drastically higher gasoline prices than us for decades, and they don't seem impoverished to me. Downgrading to a smaller and more fuel-efficient car is not a huge decrease in living standards relative to what the rest of the world has to endure.

But you're responding with the equally hyperbolic fallacy of assuming that the sum total of fossil fuel consumption and carbon output is people driving cars, and that just getting SUVs off the road would fix everything. The guilty secret of why western Europe's carbon output has dropped so much is because a lot of the dirty stuff like mining and manufacturing has been outsourced, and many of the economies have refocused on finance. Now, it doesn't take a rocket scientist to work out that not every country can do that: you cannot have a world that is solely populated by bankers. China's, India's, even Australia's carbon outputs meanwhile have shot up as their share of the manufacturing and mining (particularly mining in Australia's case) load has increased. Only this time we also have the additional carbon output of shipping stuff all the way around the world as nothing is made locally any more.

But you're responding with the equally hyperbolic fallacy of assuming that the sum total of fossil fuel consumption and carbon output is people driving cars, and that just getting SUVs off the road would fix everything.

I was cherry-picking an example; it wasn't intended to suggest a simple remedy. There are many more equally egregious wastes of energy in first-world countries; massive floodlights illuminating empty athletic fields at night are my favorite. Some of the culprits are seemingly trivial: I live in a relatively temperate climate (Northern California) where it almost never freezes, and a properly insulated residence needs minimal heating during winter. But I've ended up in several apartments or houses that were so poorly insulated that I had to choose between doubling my gas bill, or eating breakfast at 10 C. Gas is cheap, of course; insulating or rebuilding costs much more. But it isn't going to send us back to the Bronze Age; I just might have to wait another year to buy the Macbook Air. Heavily air-conditioned big-box stores are another example of extravagant waste and luxury - not that I have any moral objection to big-box stores or vapid consumerism (I also partake from time to time), but from the perspective of energy efficiency, we might as well just set gasoline on fire for fun. (Actually, we already do that: it's called NASCAR.)

More generally, we could make much better use of renewable and/or carbon-neutral energy sources (and I do include nuclear* in this category). Yes, most of these are more expensive, but none so much that we're going to suddenly find ourselves burning garbage to stay warm. The targets proposed for carbon emissions are exceedingly modest, and more than affordable for a country with huge amounts of surplus wealth. (And I don't mean that in a tax-the-rich way: even as a grad student living on a research stipend in one of the most expensive areas in the nation, I was still able to afford a car, Internet service, plane flights home on Christmas, occasional gadgets, etc., without going into debt.) I like money too, the more of it the better, but frankly, I can afford to pay more for energy if necessary, and most of the rest of the country can as well. Unless you have an absurd sense of entitlement, this is not an apocalyptic scenario.

I don't know what to suggest for the rapidly industrializing nations; it's much easier for us to adapt. However, it seems like the argument that "China won't cut back, so why should we?" is gaining increasing popularity. I don't think we should be using the Chinese government as a moral example for anything, let alone energy policy.

(* including fusion, if it ever works. It's appalling that we're spending a total of more than $300 billion on the F-35 when the industrial superpowers combined can barely get their act together to build ITER for less than €20 billion.)

If you send the nation into poverty to clean the air, people who are starving aren't going to thank you

It is pure idiotic FUD to suggest that false dichotomy: that the only two options are 1. unrestricted global climate change or 2. economic armageddon and killing grandparents in florida.

Only crazy drugged-out hippies would suggest shutting down all coal plants immediately. The smart thing to do would be to set gradual caps, adjust subsidies gradually, have reasonable, balanced goals. Maybe say "no NEW coal plants." The only way that produces economic ruin is if you're a coal company and refuse to diversify.

There is no claim that "any level of carbon in the air is too high". You made that up.

Practically no one is saying to give up transportation or electricity. You made that up, too. Some people say we should reduce wasteful transportation and electricity consumption, make its provision more efficient.

No one is sending the nation into poverty to clean the air. You made that up, too. The opposite is true: people are trying to save the nation from the poverty that Greenhouse pollution is creating, by investing in the clearly highly profitable improvements and replacements for our Greenhouse pollution ways.

No one's sneering at "money". You made that up, too. There wasn't even a sneer in there, except the one you made up. Reducing carbon emissions 10 years ago, more gradually and cheaper, doing less damage than we're facing now, would have embraced money. Just not the money of the polluters. Who deserve more than a sneer - they deserve jailtime and deep fines.

Nobody attacked your money. Unless you're profiting from Greenhouse denial or Greenhouse pollution. Which, from the pile of stuff you just made up, seems entirely likely. In which case, you deserve an attack you haven't yet gotten, as well as jailtime and deep fines.

How is climate change complicated? You increase the amount of greenhouse gasses in the atmosphere, and the planet warms. That's about as complicated as you put a blanket over you and you keep warm. Both mechanisms decrease the heat radiated away. Over 100 years ago, Arrhenius [wikipedia.org] gave estimates of global warming that closely match the latest observations. It's not complicated at all.

A quick glance at a graph of worldwide temperatures [wikipedia.org] assures me that there has been very significant warming over the past 15 years. Not to mention the melting of Arctic [nsidc.org] and Antarctic [nasa.gov] ice. So, yes, it seems just as simple as I say.

Exactly what math are you using to determine whether or not there is a statistically significant warming trend over the past 15 years?

Here's the famous Phil Jones from UEA:

"BBC: Do you agree that from 1995 to the present there has been no statistically-significant global warming

Phil Jones: Yes, but only just. I also calculated the trend for the period 1995 to 2009. This trend (0.12C per decade) is positive, but not significant at the 95% significance level. The positive trend is quite close to the significa

What makes you think that temperatures haven't increased in the last 15 years? 2010 was tied with 2005 for the hottest year in the GISS record. It's looking like 2012 will set a new record if an El Nino develops.

It took 50 years from the first Surgeon General's report on the dangers of smoking till smoking was banned here in all workplaces.

1. These kinds of massive changes take time.2. Despite all the lobbying and all the PR spin and all the PAC donations and all the flat out fucking lies spouted by the tobacco industry, in the end they lost. Per capita smoking is now about 1/3 of the peak amount and trending downward.

Only if the also predicted earthquake and the subsequent opening of the graves happens, too. They hedged against your theory. Hmm, wait... nutcase predicts opening of the graves on saturday AND the CDC publishes a zombie survival guide?? Excuse me, I am off to clean my shotgun again.

All I want to know is when the ISS crew is getting raptured, assuming there is one Real True Christian(TM) on board... I read a New Yorker interview with that nutcase Camping. Why oh why don't they ask the really interesting question like that in their interviews??

No, abuse of governmental power is the exception in our nation. The problem is one of perspective and that any abuse is a very terrible thing. Check African nations if you want to see countries where abuse is the rule. Also, don't confuse government powers that are disagreeable with abuse of power. The Department of Homeland Security, although the number 1 contender for my list of most corrupt agencies, is not itself governmental abuse. Warrentless phone tapping is, but that's ultimately a tiny part of

I haven't seen anyone propose "world government" for the solution to global warming. The solution put forward has been for countries to agree to reduce carbon dioxide emissions. Reducing carbon dioxide emissions will increase costs, but effects of global warming will increase costs, too. The debate is what amount of spending on reducing carbon dioxide emissions will minimize total costs.

I haven't read and cant give specific evidence... but neither can you. That should have told you to go do some research and make an informative post, but instead, you've decided to maintain your ignorance and maintain ours to boot.

In a nutshell, because the thermal, i.e. kinetic energy of atmospheric molecules is way too high to get separation by weight. They are moving in random directions too fast to settle down. As for the ozone layer being where it is, yes, it is being produced up there. The layer is a dynamic process - ozone being produced from oxygen by UV activation and reacting back. You get the layer at a certain height where you have the right balance of O2 concentration and UV intensity. CFCs are a catalyst that shift that equilibrium to the side of oxygen, removing the conditions that lead to the dynamic formation of the layer in the first place.

I doubt that your hypothesis of mere thermal energy preventing separation by weight is correct. It's likely that an isolated column of air would separate by weight. As long is there isn't macroscopic circulation to stir the air (wind, jet stream, etc.), there can be stratification by temperature such that freezing occurs in a valley but not half way up an adjacent hill. There have been cases of people dying by asphyxiation when a volcanic vent produced a lot of CO2, which settled down to a nearby lake, driv

Depends on the molecular species in question - e.g. hydrogen will reach escape velocity just from the thermal velocity distribution. You are completely right that I neglected convective mixing in the post above, which of course is a strong effect. If you release a lot of heavy gas at once, yes, you get layering. But even that might diffuse out given the long timescales which you need to take into account when talking about the atmosphere as whole. I just wanted to give the nutshell presentation. It's nearly

The difference between the North Polar region and the South Polar region is that the Arctic is an ocean surrounded by land and covered by ice and Antarctica is land surrounded by ocean with ice sheets built up on it. It's considerably colder in Antarctica. The two regions are not really very comparable when you get into details. The Wikipedia article on ozone depletion [wikipedia.org] has an explanation about the cause of the ozone hole. The northern hemisphere atmosphere and southern hemisphere atmosphere are somewhat

That's where it gets somewhat complicated. While I have a pretty good grasp of the chemistry involved, I am a dilettante when it comes to atmospheric dynamics on the large scale. The stratospheric conditions over Antarctica seem to be particularly good for activating chlorine compounds into the catalytically active ClO-radicals. Cooling of the air in winter leads to sinking of the air masses which then, via the coriolis effect, form a very stable vortex that lasts into summer. This polar vortex isolates the

As someone else said the atmosphere isn't stationary long enough for the constituent elements to separate into layers by weight. It's like asking why sediment in moving water doesn't settle out immediately.

Also consider this, Ozone is also a product of combustion products (smog) being mixed with high temperatures air (summer). Ozone is actually a pollutant monitored by the clean air act that LA frequently violates in the summer. So why doesn't all that ozone float up and fill the hole in? Because if it's no

Mechanizes, evidence and prediction. They all came true. This is exactly what was predicted.

It was CFC, and I am sick and tired of you poor excuses for a limp wristed cum stains not even bothering to look at the research and data, yes still thinking your opinion on the matter deserves equal weight in the matter. You're opinion deserves no weight on this matter, and it is provable wrong.

The little guy in this case being the multinational conglomerates that produced it and lobbied their asses off to prevent the banning. You are an idiot. The evidence and proof of CFC's destroying the ozone layer is in the science journals. It involves thousands of research projects including sampling the layer (including the CFC's in it) to year on year measurements to the simple chemical reaction formula that shows it's possible. It was proven beyond a shadow of a doubt to the entire community of scientist

Nice crackpot you found there. My favourite - his acid rain piece. "Decades of monitoring to detect an effect". Right. Tell that to the deforested mountain ridges in my home county that have recovered just fine after SO2 was essentially removed from coal plant exhaust. As for that nature reference - you conveniently omit that this is not a paper, but a news blurb. Serious papers on the issue? Well, rather thin in that department. I met Paul Crutzen on several occasions and had some nice talks with him. Calling him a tool of special interest lobbying is quite... off the mark.

SO2 is insofar part of the subject in question as the crackpot mentioned above rants about acid rain not existing in the quoted blog. As for the references. Yes, ClOOCl photolysis under stratospheric conditions modelled in the lab is by a factor 6 lower than previously predicted. So? To quote the abstract of the paper in question: "This large discrepancy calls into question the completeness of present atmospheric models of polar ozone depletion" - true that. At no point, the basic mechanism is questioned, though. To quote the part of Rex' quote you conveniently omitted: "Overwhelming evidence still suggests that anthropogenic emissions of CFCs and halons are the reason for the ozone loss.". In summary - you and the crackpot above take part of the usual scientific process, which is characterized by continuous refinement of models, out of context and construct a fundamental disagreement from it, which never existed in the first place. Basic propaganda tool.

The SO2 and trees are relevant because they are another article by the same person. While it is possible for some truth to be found in a forest of lies, it's not a good place to go looking for it.

That said, there were a lot of errors made by those who proclaimed that acid rain was a serious problem. In addition, there was plenty of reason to reduce sulphur emissions beyond the fact that SO2 forms suphurous acid: SO2 is a poison by itself, as is H2S in sufficient concentration.